Remove: Testdata folder/ Add: Testing readme

See merge request !132

Fix: File is being used by another process error on atomic write.

See merge request !131

1. Update: Testing readme

1. Update: gitignore to ignore testingdata folder

1. Remove: Test data folder because of size
2. Add: Testing guide in Testing.md

1, Fix: File is being used by another process error on atomic write. Closed temporary file conditionally,

Add: Redis as a cache to support grid mode

See merge request !130

1. Add: Exit if connection to redis server failed

1. Add: marshal with type check version. This saves allocations and time if existing data is string or []byte.
2. Fix: Typos.
3. Add: Benchmarks for marshal and marshalWithTypeCheck

1. Add: Check redis connection on setup

1. Add: Save by adding provided prefix.
2. Add: Set() method will add default expiration time.

1. Add: Purge redis cache

1. Add: Redis cache to cache configuration

1. Refactor: Unit tests

Add: Unit tests

1. Fix: panic in redis cache object is nil

added encryption support in fdb

See merge request !128

1. Add: Redis as a cache support for grid mode. Redis implements cacher interface.

1. Add: Cacher interface and cache types. Fastcache implements this interface.

* added encryption support in fdb 
* added feature of dynamic encryption key generation function

fix: fdb delete record

See merge request !126

segregation of pack operation and fdb operations

See merge request !124

added global lock for lazy write in append  bucket 

* removed unused code
* added lock for reading pack file

moved packfile related functions in filemdl and done changes in fdb accordingly

Fix: Error suppressed in CallService()

Closes #5

See merge request !123

1. Fix: Error suppressed in CallService(). This makes users unaware of the actual error from called service.

fix: fail to write fdb index lazily

See merge request !122

added defer for closing file

See merge request !121

File lock code commented

See merge request !120

File lock code commented

added filelock while performing data manipulation on fdb bucket

See merge request !118